1. Field of the Invention
The present invention relates to a waterproofing structure for a connector, and particularly relates to a waterproofing structure that seals a gap between connectors without any rubber packing.
2. Description of the Related Art
In the background art, a waterproof connector for connecting different electric wires with each other is mounted on a moving body such as a motorcycle. Such a connector is arranged to include a male housing and a female housing. The male housing receives a male terminal to which an electric wire is connected. The female housing receives a female terminal to which another electric wire is connected. When the male housing is inserted and fitted into the female housing, a gap is formed between the outer circumferential surface of the male housing and the inner circumferential surface of the female housing. A rubber packing is provided in the gap between the housings so as to prevent water from invading though the gap.
On the other hand, JP-A-2009-146659 discloses a waterproofing structure for a connector for sealing housings from each other without using any rubber packing. In the waterproof connector, a cylindrical inner hood portion is circumferentially enclosed by an outer hood portion to thereby form one of the housings. Annular seal protrusion portions are provided in both the inner circumferential surface and the outer circumferential surface of an outer cylinder respectively to thereby form the other housing.
According to the waterproof connector, when one housing is inserted and fitted to the other housing, the seal protrusion portion in the outer circumferential surface of the outer cylinder is brought into circumferential contact with the inner circumferential surface of the outer hood portion, and the seal protrusion portion in the inner circumferential surface of the outer cylinder is brought into circumferential contact with the outer circumferential surface of the inner hood portion. Thus, a waterproofing structure is formed at two places, that is, in a gap between the outer hood portion and the outer cylinder and in a gap between the inner hood portion and the outer cylinder. It is therefore possible to secure waterproofness without using any rubber packing.
However, when the housings are to be assembled with each other in the case of the waterproofing structure according to JP-A-2009-146659, the seal protrusion portions of the other housing move pressing the hood portions of the one housing respectively. Accordingly, due to friction between the seal protrusion portions and the hood portions, there arises a problem that the fitting load with which the housings are fitted to each other becomes large enough to increase the burden of the assembling work.
In addition, each seal protrusion portion abutting against the inner hood portion or the outer hood portion may be shaved. In this case, when shavings of the seal protrusion portion are put into a gap between the two housings, there is a fear that the housings cannot be fitted to each other in a regular position. Further, when the seal protrusion portion abutting against the inner hood portion or the outer hood portion is deformed, there is a fear that the force with which the seal protrusion portion can press the inner circumferential surface or the outer circumferential surface of the outer cylinder may be reduced to lower the sealing performance.